Tendon prosthesis



Dec. 8, 1970 UER; JR 3,545,008-

TENDON PRQSTHESIS Filed May 27, 1968 i .v awn roe.

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United States Patent O 3,545,008 TENDON PROSTHESIS Karl F. Bader, In,Chicago, Ill. (2300 N. Rockton Ave., Rockford, Ill. 61101) Filed May 27,1968, Ser. No. 732,404 Int. Cl. A61f 1/24 US. Cl. 3-1 6 Claims ABSTRACTOF THE DISCLOSURE A tendon prosthesis for use in tendon surgeryparticularly where there is complete or extensive loss of the tendon,structurally including an elongated member made from a flexible,chemically inert material having at least one flap at each end adaptedto overlap the tendon and means for firmly anchoring the prosthesis tothe tendon providing a strong, functional anastamotic union.

SUMMARY OF THE INVENTION 14 at each end adapted to overlap a repaired orreconstructed tendon 16. In addition a suture material 18 isincorporated within the elongated member 12 and each flap 14 has a meshor netting 20 on its inner surface as shown in FIGS. 1 and 2.

As shown in the figures the tendon prothesis 10 is preferably anelongated member 12, however, it may be fabricated to any desired sizeand shape. The elongated member 12 is preferably fabricated from asheeting material and may be reinforced as shown in FIG. 2 by a Dacronmesh 15 or similar material. The reinforcing increases the strength ofthe elongated member and prevents stretching during suture attachment.In addition, the elongated member 12 may be modified by the doctorsculpturing it to any desired size and shape at the time of surgery.

It is extremely important that the material used to form the elongatedmember 12 be substantially inert to prevent foreign body reactions. Inaddition the material must be compatible with the physiologicalprocesses of the human body and preferably has nonwetting surfaces whichminimize sticking or encrustation. Further the material A further objectis a full-function tendon prosthesis which is able' to withstand fullWeight bearing capacity without separation or deformity.

Another object is a tendon prosthesis which is chemically inert anddemonstrates a very low order of reactivity eliminating anyincapacitating foreign body reactions.

Another object is a versatile tendon prosthesis which is adaptable to avariety ofclinical situations including instances of soft tissueavulsion, severe infection, electrical burn and surgical resection.

Another object is an improved tendon prosthesis which substantiallyeliminates adhesions and allows the patient to regain full range ofmotion including the ability for full active extension and flexion.

Another object is a tendon prosthesis which may be easily positioned andone positioned moves through the surrounding tissue with littleresistance.

Another object is an improved method of constructing a strong anddurable tendon prosthesis which necessitates no further surgicaloperations.

Other objects and advantages will be apparent from the ensuringspecification and drawing for this invention.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERREDEMBODIMENTS Referring to the drawing in more detail it will be seen thatthis invention basically includes an elongated member 12 made from asubstantially inert material having flaps should contain the quality ofnonadherence to tissue and is preferably resistant to adsorption,hardening and degeneration. A flexible silicone elastomer manufacturedby Dow Corning sold under the trademark Silastic has been found tosubstantially meet the above mentioned qualifications. In addition othermedical-grade silicone elastomers, or material similar to Silastic orequivalents thereof have been found as satisfactory material for theelongated member 12.

As best shown in FIGS. 1 and 2 a suture material 18 may be fabricatedwithin the elongated member 12 by bonding two or more layers of sheetingmaterial around the suture material. The ends of the prosthesis 10 arethen spread apart to form a pair of flaps 14 for overlapping therepaired or reconstructed tendon. On the inside surface of each flap 14there is secured a mesh or netting 20 formingsuitable end plates fortendon anastamosis. The flaps 14 with the mesh or netting 20 are devisedto facilitate rapid and accurate areas of anastamosis with minimalexposure.

It is important that the mesh or netting 20 be made from a material ormaterials that cause fibroblastic infiltration to occur between thesevered ends of the tendon 16 and the mesh 20 therebyfirmly anchoringthe prothesis 10 With a strong, functional anastamotic union. One suchmaterial is polyester, however, similar materials or equivalents thereofhave been found as a satisfactory mesh materal.

FIGS. 3 and 4 show how the suture attachment is performed in moredetail. The flaps 14 overlap the tendon 16 with the mesh materialresting against the outer surface of the tendon while the suturematerial 18 may be attached to each end of the tendon as shown in thesefigures. It should again be noted that the suture material 18 runs thefull-length of the prosthesis 10 providing a strong durable means forattaching the prosthesis. The fibroblastic infiltration which occursbetween the severed tendon 16 and the mesh 20 of each flap insures astrong, functional anastamotic union.

The use, operation and function of this invention are as follows:

The results from experiments and clinical use of this invention havebeen very favorable. The tendon prosthesis 10 allows the patient toregain essentially full range of motion within a short time after castremoval. In addition the prosthesis does not cause restrictiveadhesions, infections or extrusions. Further, the tendon prosthesis canwithstand full weight bearing capacity with no gross deformity includingthe ability for full active extension and flexion.

On reexploration of experimental uses of this inven tion each of thetendon prostheses were in good position and completely covered with alayered fibroblastic membrane. This delicate membrane was vascularizedand substantially resembled normal synovial tissue. In fact theappearance of the entire tendon prosthesis is very similar to a normaltendon.

Functionally, the tendon prosthesis, and to a lesser degree itsfibroblastic membrane, were found to move through the surrounding tissuewith very little resistance. When the membrane was dissected, therespected tendon ends were noted to be firmly anchored to the prosthesisby the mesh material of the end flaps 14. In addition the membraneencasing, caused by the material of the elongated member, extendeddistally and around the normal tendon to reinforce the anastamosis.

It should be emphasized that the tendon prosthesis 10 was designedprimarly as a full-function tendon after only one surgical procedure.Further surgical operations such as revision or replacement are notcontemplated with this invention. However, it may be noted that ifseparation of an anastamosis did occur, it could be removed easily andthe reactive membrane formed around the prosthesis could be utilized asa sheath for an autologous graft.

I claim:

1. A tendon prosthesis for replacement of the damaged portion of atendon as a full-function tendon including:

an elongated member made from a flexible substantially inert materialthat is compatible with the physiological processes of the human body;

a pair of flaps in opposed relationship at each end of the elongatedmember, said flaps being integral withv the elongated member and havingan inside surface for enveloping the severed ends of the tendon and anoutside surface designed for movement in the surrounding body tissue;

a mesh material secured to the inside surface of each flap adapted tocontact only the severed ends of the tendon to form .a strong,functional anastamotic union, said mesh material being separated fromthe surrounding body tissue by the flaps; and

suture means running longitudinally the full-length of the prosthesisand extending beyond the end flaps for initially attaching theprosthesis to the tendon.

2. The structure of claim 1 further characterized in that the elongatedmember including the end flaps is made from a nonwetting, nonreactivematerial.

3. The structure of claim 1 further characterized in that the elongatedmember including the end flaps is made from a medical-grade siliconeelastomer.

4. The structure of claim 1 further characterized in that the elongatedmember including the end flaps is reinforced with a mesh material toincrease its strength.

5. The structure of claim 1 further characterized in that the meshmaterial is made from a polyester adapted to cause fibroblasticinfiltration therethrough, thereby anchoring the prosthesis to thesevered ends of the tendon.

6. In a tendon prosthesis for use in repairing a damaged tendon, theprocess of making the prothesis including the steps of:

bonding together a plurality of layers of medical-grade siliconeelastomer sheeting over a suture material ex tending length-wisetherein;

fabricating an elongated member from the medicalgrade silicone elastomersheeting;

separating the distal ends of the prosthesis to a desired length to formend flaps having an inner surface and an outer surface, said innersurface being adapted to overlap the severed tendon;

placing a polyester mesh on the inner surface of each end flap forcontacting only the severed ends of the tendon and thereby beingseparated from the surrounding body tissue by the end flap; and

bonding the polyester mesh to the inner surface of each end flap.

References Cited UNITED STATES PATENTS 3,176,316 4/1965 Bodell 3-13,197,788 8/1965 Segger 31 OTHER REFERENCES RICHARD A. GAUDET, PrimaryExaminer R. L. FRINKS, Assistant Examiner US. Cl. X.R.

